Ryan Phillippe is NOT listed as the father on the birth certificate -- but the actor is still a huge influence on the baby his ex-GF says is his ... because she gave the little tike Ryan's last name.

According to the birth certificate, obtained by TMZ, Ryan's ex Alexis Knapp gave birth to a baby girl named Kailana Phillippe-Knapp on July 6. The certificate does NOT list a father.

Ryan's still waiting on DNA results proving he's the daddy -- but it seems he's mostly convinced ... since he was reportedly at Knapp's bedside when she gave birth.

He hasn't taken a DNA test to prove he's the father -- but Ryan Phillippe is already playing daddy with his soon-to-pop ex-girlfriend ... months after she claimed he left her high and dry with the baby.



According to sources, Ryan and ex-GF Alexis Knapp -- who's due any day now -- stopped for some coffee before hitting up the gynecologist's office in L.A. yesterday ... together.

Knapp insists Ryan is the father -- but the actor refuses to submit to a DNA test until the baby is born ... to prevent any pre-natal complications.

It's the first time the ex-couple has been seen out since Knapp hired a lawyer in March, claiming Ryan saddled her with all the baby's medical expenses -- an allegation Ryan has denied.

At least we know what he did this summer.

Ryan Phillippe and girlfriend Amanda Seyfried were spotted leaving Amika Nightclub on High Street in London last night after an evening on the town.


Their relationship is strong on any continent.

Ryan Phillippe's ex/alleged baby mama has lawyered up ... and a legal battle is now brewing ... TMZ has learned. 



Alexis Knapp -- the model/actress who claims to be carrying Ryan's baby -- has hired Mark Vincent Kaplan.

Ryan has said he'll take a DNA test once the baby is born and support the child if it's his, but Alexis is not satisfied.

And here's a fun fact.  Kaplan repped K-Fed in his divorce/custody battle with Britney Spears.

While Alexis Knapp claims she's carrying his unborn child, a very buff and carefree Ryan Phillippe went for a hike in the Hollywood Hills with his lady friend Amanda Seyfried on Wednesday.



It's an uphill battle.

The woman who claims Ryan Phillippe is her soon-to-be baby daddy says Ryan is a pre-natal deadbeat dad because he hasn't paid any of her expenses ... but we're told that's just not the case.



Alexis Knapp says her baby -- due in June -- is definitely Ryan's.  For his part, Ryan says he'll take a DNA test when the baby is born and if it's his ... he'll step up and support the kid.

But sources connected to Alexis claim while she's been incubating, she hasn't received a dime from Ryan and she's hurting financially because she's unable to work.

But sources connected to Ryan tell us Alexis is lying -- that Ryan has been paying Alexis' expenses, despite the fact that he has no obligation to do so until a judge establishes paternity.

We're also told Ryan is furious, because Alexis agreed that if Ryan paid to support her during her pregnancy, she wouldn't go blabbing to the media -- which Ryan's people believe she has done.

As one source connected to Ryan put it, "File this under the category, 'No good deed goes unpunished.'"

Now that Ryan Phillippe allegedly knocked up someone who's NOT named Reese -- we gotta ask ... why the hell don't famous dudes wear friggin' condoms? TMZ investigates.




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Ryan Phillippe will "gladly" take a DNA test to determine if he's the baby daddy of a woman he had been seeing ... this according to sources directly connected to Ryan.


We're told Ryan will not submit to the DNA test until the baby is born.  There are prenatal paternity tests, but there's a slight risk of miscarriage and Ryan does not want to take the chance.

Our sources say Ryan will step up and provide support for Alexis Knapp's unborn baby, provided it is indeed his.

Although there are reports Ryan and Alexis were boyfriend/girlfriend, we're told that was never the case. They had dated for a while but it was never serious.

The baby is due in June. 

It was a trifecta of hot Ryans as Ryan Phillippe, Gosling and Reynolds all got shady at they arrived to different airports this week.




Question is ...

Ryan Phillippe let it all air out while in L.A. yesterday.


The 35-year-old was flying low.

"MacGruber" star Ryan Phillippe has the hit of the summer on his hands ... and by that we mean his smokin' hot body.



The 35-year-old father of two soaked his smooth, ripped and tatted up muscles in the waters of the Caribbean this weekend.

It's a blockbuster.